ABSTRACT:The Partnership for Advanced Computing in Europe (PRACE) aims to provide a persistent pan-European HPC service, consisting of several tier-0 centres. The PRACE Project Preparatory Phase successfully completed all legal, administrative, and technical preparation work for the target HPC service. Now the project has moved to the Implementation Phase. The Work Package 6 (WP6) of PRACE Preparatory Phase was responsible for the applications enabling on Petaflop/s systems. A set of representative applications from a wide variety of application areas were selected into the PRACE Application Benchmark Suite (PABS). The PABS applications were ported to a number of PRACE prototype systems and their requirements for petascale architectures were captured. The PABS applications scalability and optimisation strategies for petascaling were also investigated. This poster shows the enabling work done for the PABS applications NAMD (from UIUC, US) and HELIUM (from Queen's University Belfast, UK) on several PRACE prototypes.